package com.cypher.encryptionanddecryption.util;

import org.apache.commons.lang3.StringUtils;

/**
 * 16进制数据计算、校验、转换等工具类
 * @author: 古霸天
 * @date: 2020/11/19
 */
public class HexUtils {
    public static final char[] hexCode = "0123456789ABCDEF".toCharArray();
    /**
     * A5异或
     * @param data
     * @return
     */
    public static String hexOrA5(String data) {
        StringBuffer result = new StringBuffer();
        for (int i = 0; i < data.length() / 2; i++) {
            // 进行A5异或
            int a5Result = 0xA5 ^ Integer.parseInt(data.substring(i * 2, 2 * (i + 1)), 16);
            result.append(intToHex(a5Result, 2).toUpperCase());
        }
        return result.toString();
    }

    /**
     * CRC16加密
     * @param bytes
     * @return
     */
    public static String crc16(byte[] bytes) {
        int crc = 0;
        byte da;
        for (int i = 0; i < bytes.length; i++) {
            da = (byte) (crc >> 8);
            crc <<= 8;
            crc ^= crcArray[0xFF & (da ^ bytes[i])];
        }
        return intToHex(crc, 8).substring(4).toUpperCase();
    }
    /**
     * crc多项式
     */
    public static final int[] crcArray = new int[]{
            0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
            0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
            0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
            0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
            0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
            0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
            0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
            0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
            0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
            0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
            0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
            0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
            0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
            0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
            0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
            0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
            0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
            0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
            0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
            0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
            0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
            0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
            0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
            0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
            0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
            0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
            0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
            0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
            0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
            0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
            0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
            0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
    };

    /**
     * 十进制转换16进制
     * @param data  数据
     * @param length    需要转换16进制的位数
     * @return
     */
    public static String intToHex(int data, int length) {
        String chars = Integer.toHexString(data);
        int charLength = chars.length();
        if (charLength > length) return chars;

        int diff = length - charLength;
        StringBuffer buf = new StringBuffer();
        for(int i = 0; i < diff; i++) {
            buf.append("0");
        }

        return buf.toString() + chars;
    }

    /**
     * 16进制转byte
     * @param data
     * @return
     */
    public static byte[] hexToBytes(String data) {
        data = data.replace(" ", "");
        byte[] bytes = new byte[data.length() / 2];
        for(int i=0; i < data.length() / 2; i++) {
            bytes[i] = (byte) Integer.parseInt(data.substring(i * 2, 2 * (i + 1)), 16);
        }
        return bytes;
    }

    /**
     * 16进制转byte，并指定byte长度
     * @param data 需要转换的数据
     * @param byteLength byte长度
     * @return
     */
    public static byte[] hexToBytes(String data, int byteLength) {
        data = data.replace(" ", "");
        int len = byteLength;
        if (data.length() > len) {
            len = data.length();
        }
        byte[] bytes = new byte[len];
        for(int i=0; i < data.length() / 2; i++) {
            bytes[i] = (byte) Integer.parseInt(data.substring(i * 2, 2 * (i + 1)), 16);
        }
        return bytes;
    }
    /**
     * byte数组转16进制
     * @param bytes
     * @return
     */
    public static String bytesToHex(byte[] bytes) {
        StringBuilder hexStr = new StringBuilder();
        for(int i = 0 ; i <bytes.length; i++) {
            hexStr.append(hexCode[bytes[i] >> 4 & 0xf])
                    .append(hexCode[bytes[i] & 0xf]);
        }
        return hexStr.toString().trim();
    }

    /**
     * 16进制数据格式化， 每组之间增加空格
     * @param content
     * @return
     */
    public static String formatHex(String content) {
        // 有空格先去除空格
        content = content.replace(" ", "");
        StringBuffer buf = new StringBuffer();
        for(int i = 0; i < content.length() / 2; i++) {
            buf.append(StringUtils.substring(content, 2 * i, 2 * (i + 1)));
            buf.append(" ");
        }
        return buf.toString().trim().toUpperCase();
    }

    /**
     * 16进制数据去掉空格
     * @param content
     * @return
     */
    public static String trimHex(String content) {
        return content.replace(" ", "");
    }

    /**
     * 反转数据
     * @param data
     * @return
     */
    public static String hexReverse(String data) {
        StringBuffer buf = new StringBuffer();

        for (int i = 0; i < data.length(); i++) {
            buf.append(StringUtils.substring(data, data.length() - i * 1 - 1, data.length() - i * 1));
        }

        return buf.toString();
    }

    /**
     * 在数据左边
     * 数据长度小于bits的用0补齐
     * @param data 需要填充的数据
     * @param bits 填充到多少位
     * @return
     */
    public static String paddingLeft(String data, int bits) {
        return getPadData(data, bits) + data;
    }

    /**
     * 在数据右边
     * 数据长度小于bits的用0补齐
     * @param data
     * @param bits
     * @return
     */
    public static String paddingRight(String data, int bits) {
        return data + getPadData(data, bits);
    }

    /**
     * 得到补齐数字
     * @param data
     *  原数据
     * @param bits
     *  补齐长度
     * @return
     */
    public static String getPadData(String data, int bits) {
        return getPadData(data, "0", bits);
    }

    /**
     * 获得补齐数字
     * @param data
     *  原数据
     * @param padStr
     *  需要补齐的文字
     * @param bits
     *   补齐长度
     * @return
     */
    public static String getPadData(String data, String padStr, int bits) {
        int dataLength = data.length();
        if (dataLength == bits || dataLength > bits) return "";

        int diff = bits - dataLength;
        StringBuffer buf = new StringBuffer();
        for(int i = 0; i < diff; i++) {
            buf.append(padStr);
        }
        return buf.toString();
    }
    /**
     * 16进制转明文
     * @param data
     * @return
     */
    public static String ascToStr(String data) {
        StringBuffer buf = new StringBuffer();
        for (int i = 0; i < data.length() / 2 ; i++) {
            String ch = data.substring(2 * i, 2 * (i + 1));
            if (!StringUtils.equals("00", ch)) {
                buf.append((char) Integer.parseInt(ch, 16));
            }
        }
        return buf.toString();
    }

    /**
     * 明文转16进制
     * @param data
     * @return
     */
    public static String strToAsc(String data) {
        StringBuffer buf = new StringBuffer();

        byte[] bytes = data.getBytes();
        int len = bytes.length;
        for (int i = 0; i < bytes.length; i++) {
            buf.append(paddingLeft(Integer.toHexString(bytes[i]), 2));
        }
        return buf.toString().toUpperCase();
    }

    /**
     * 浮点型转换为16进制
     * @param doubleStr
     *      小数字符串
     * @param decimalDigits
     *      小数点后位数
     * @param hexDigits
     *      16进制位数
     * @return
     */
    public static String doubleToHex(double doubleStr, int decimalDigits, int hexDigits) {
        // 如果小数点位数为0，则直接做整形转换
        if (decimalDigits <= 0) {
            return paddingLeft(Integer.toHexString((int) doubleStr), hexDigits);
        }

        return paddingLeft(Integer.toHexString(doubleToInteger(doubleStr, decimalDigits)), hexDigits);
    }

    /**
     * 浮点型转换成整形
     * @param data
     *      浮点型数字
     * @param decimalDigits
     *      小数点后位数，
     * @return
     *      例如小数点位数为1 结果返回 小数*10
     *      位数为2 结果返回 小数*100
     */
    public static int doubleToInteger(double data, int decimalDigits) {
        if (decimalDigits <= 0) {
            return (int) data;
        }
        return (int) (data * Integer.parseInt(padLeft("1", "0", decimalDigits)));
    }

    public static double integerToDouble(int data, int decimalDigits) {

        if (decimalDigits <= 0) {
            return data;
        }
        return (double) data / Integer.parseInt(padLeft("1", "0", decimalDigits));
    }

    /**
     * 获取格式化后的浮点数
     * @param data
     * @param decimalDigits
     * @return
     */
    public static String getFormatDouble(int data, int decimalDigits) {
        return formatDouble(integerToDouble(data, decimalDigits), decimalDigits);
    }
    /**
     * 格式化浮点型小数点位数
     * @param data
     * @param digits
     * @return
     */
    public static String formatDouble(double data, int digits) {
        return String.format("%." + digits + "f", data);
    }

    /**
     * 左对齐补充内容
     * @param data
     * @param digits
     * @return
     */
    public static String padLeft(String data, String replenishStr, int digits) {
        StringBuffer multiple = new StringBuffer(data);
        for (int i = 0; i < digits; i++) {
            multiple.append(replenishStr);
        }
        return multiple.toString();
    }

    /**
     * 获取数组下表
     * @param codes
     * @param data
     * @return
     */
    public static int getArrayIndex(String[] codes, String data) {
        int index = -1;
        for (int i = 0; i < codes.length; i++) {
            if (StringUtils.equals(data, codes[i])) {
                index = i;
            }
        }
        return index;
    }
}
